/*
 * Copyright (C) 2009 Texas Instruments.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * common vpss driver for all video drivers.
 */
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/compiler.h>
#include <linux/io.h>
#include <mach/hardware.h>
#include <media/davinci/vpss.h>

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("VPSS Driver");
MODULE_AUTHOR("Texas Instruments");

/* DM644x defines */
#define DM644X_SBL_PCR_VPSS		(4)

/* vpss BL register offsets */
#define DM355_VPSSBL_CCDCMUX		0x1c
/* vpss CLK register offsets */
#define DM355_VPSSCLK_CLKCTRL		0x04
/* masks and shifts */
#define VPSS_HSSISEL_SHIFT		4

/*
 * vpss operations. Depends on platform. Not all functions are available
 * on all platforms. The api, first check if a functio is available before
 * invoking it. In the probe, the function ptrs are intialized based on
 * vpss name. vpss name can be "dm355_vpss", "dm644x_vpss" etc.
 */
struct vpss_hw_ops {
	/* enable clock */
	int (*enable_clock)(enum vpss_clock_sel clock_sel, int en);
	/* select input to ccdc */
	void (*select_ccdc_source)(enum vpss_ccdc_source_sel src_sel);
	/* clear wbl overflow bit */
	int (*clear_wbl_overflow)(enum vpss_wbl_sel wbl_sel);
};

/* vpss configuration */
struct vpss_oper_config {
	__iomem void *vpss_bl_regs_base;
	__iomem void *vpss_regs_base;
	struct resource		*r1;
	resource_size_t		len1;
	struct resource		*r2;
	resource_size_t		len2;
	char vpss_name[32];
	spinlock_t vpss_lock;
	struct vpss_hw_ops hw_ops;
};

static struct vpss_oper_config oper_cfg;

/* register access routines */
static inline u32 bl_regr(u32 offset)
{
	return __raw_readl(oper_cfg.vpss_bl_regs_base + offset);
}

static inline void bl_regw(u32 val, u32 offset)
{
	__raw_writel(val, oper_cfg.vpss_bl_regs_base + offset);
}

static inline u32 vpss_regr(u32 offset)
{
	return __raw_readl(oper_cfg.vpss_regs_base + offset);
}

static inline void vpss_regw(u32 val, u32 offset)
{
	__raw_writel(val, oper_cfg.vpss_regs_base + offset);
}

static void dm355_select_ccdc_source(enum vpss_ccdc_source_sel src_sel)
{
	bl_regw(src_sel << VPSS_HSSISEL_SHIFT, DM355_VPSSBL_CCDCMUX);
}

int vpss_select_ccdc_source(enum vpss_ccdc_source_sel src_sel)
{
	if (!oper_cfg.hw_ops.select_ccdc_source)
		return -1;

	dm355_select_ccdc_source(src_sel);
	return 0;
}
EXPORT_SYMBOL(vpss_select_ccdc_source);

static int dm644x_clear_wbl_overflow(enum vpss_wbl_sel wbl_sel)
{
	u32 mask = 1, val;

	if (wbl_sel < VPSS_PCR_AEW_WBL_0 ||
	    wbl_sel > VPSS_PCR_CCDC_WBL_O)
		return -1;

	/* writing a 0 clear the overflow */
	mask = ~(mask << wbl_sel);
	val = bl_regr(DM644X_SBL_PCR_VPSS) & mask;
	bl_regw(val, DM644X_SBL_PCR_VPSS);
	return 0;
}

int vpss_clear_wbl_overflow(enum vpss_wbl_sel wbl_sel)
{
	if (!oper_cfg.hw_ops.clear_wbl_overflow)
		return -1;

	return oper_cfg.hw_ops.clear_wbl_overflow(wbl_sel);
}
EXPORT_SYMBOL(vpss_clear_wbl_overflow);

/*
 *  dm355_enable_clock - Enable VPSS Clock
 *  @clock_sel: CLock to be enabled/disabled
 *  @en: enable/disable flag
 *
 *  This is called to enable or disable a vpss clock
 */
static int dm355_enable_clock(enum vpss_clock_sel clock_sel, int en)
{
	unsigned long flags;
	u32 utemp, mask = 0x1, shift = 0;

	switch (clock_sel) {
	case VPSS_VPBE_CLOCK:
		/* nothing since lsb */
		break;
	case VPSS_VENC_CLOCK_SEL:
		shift = 2;
		break;
	case VPSS_CFALD_CLOCK:
		shift = 3;
		break;
	case VPSS_H3A_CLOCK:
		shift = 4;
		break;
	case VPSS_IPIPE_CLOCK:
		shift = 5;
		break;
	case VPSS_CCDC_CLOCK:
		shift = 6;
		break;
	default:
		printk(KERN_ERR "dm355_enable_clock:"
				" Invalid selector: %d\n", clock_sel);
		return -1;
	}

	spin_lock_irqsave(&oper_cfg.vpss_lock, flags);
	utemp = vpss_regr(DM355_VPSSCLK_CLKCTRL);
	if (!en)
		utemp &= ~(mask << shift);
	else
		utemp |= (mask << shift);

	vpss_regw(utemp, DM355_VPSSCLK_CLKCTRL);
	spin_unlock_irqrestore(&oper_cfg.vpss_lock, flags);
	return 0;
}

int vpss_enable_clock(enum vpss_clock_sel clock_sel, int en)
{
	if (!oper_cfg.hw_ops.enable_clock)
		return -1;

	return oper_cfg.hw_ops.enable_clock(clock_sel, en);
}
EXPORT_SYMBOL(vpss_enable_clock);

static int __init vpss_probe(struct platform_device *pdev)
{
	int status, dm355 = 0;

	if (!pdev->dev.platform_data) {
		dev_err(&pdev->dev, "no platform data\n");
		return -ENOENT;
	}
	strcpy(oper_cfg.vpss_name, pdev->dev.platform_data);

	if (!strcmp(oper_cfg.vpss_name, "dm355_vpss"))
		dm355 = 1;
	else if (strcmp(oper_cfg.vpss_name, "dm644x_vpss")) {
		dev_err(&pdev->dev, "vpss driver not supported on"
			" this platform\n");
		return -ENODEV;
	}

	dev_info(&pdev->dev, "%s vpss probed\n", oper_cfg.vpss_name);
	oper_cfg.r1 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!oper_cfg.r1)
		return -ENOENT;

	oper_cfg.len1 = oper_cfg.r1->end - oper_cfg.r1->start + 1;

	oper_cfg.r1 = request_mem_region(oper_cfg.r1->start, oper_cfg.len1,
					 oper_cfg.r1->name);
	if (!oper_cfg.r1)
		return -EBUSY;

	oper_cfg.vpss_bl_regs_base = ioremap(oper_cfg.r1->start, oper_cfg.len1);
	if (!oper_cfg.vpss_bl_regs_base) {
		status = -EBUSY;
		goto fail1;
	}

	if (dm355) {
		oper_cfg.r2 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
		if (!oper_cfg.r2) {
			status = -ENOENT;
			goto fail2;
		}
		oper_cfg.len2 = oper_cfg.r2->end - oper_cfg.r2->start + 1;
		oper_cfg.r2 = request_mem_region(oper_cfg.r2->start,
						 oper_cfg.len2,
						 oper_cfg.r2->name);
		if (!oper_cfg.r2) {
			status = -EBUSY;
			goto fail2;
		}

		oper_cfg.vpss_regs_base = ioremap(oper_cfg.r2->start,
						  oper_cfg.len2);
		if (!oper_cfg.vpss_regs_base) {
			status = -EBUSY;
			goto fail3;
		}
	}

	if (dm355) {
		oper_cfg.hw_ops.enable_clock = dm355_enable_clock;
		oper_cfg.hw_ops.select_ccdc_source = dm355_select_ccdc_source;
	} else
		oper_cfg.hw_ops.clear_wbl_overflow = dm644x_clear_wbl_overflow;

	spin_lock_init(&oper_cfg.vpss_lock);
	dev_info(&pdev->dev, "%s vpss probe success\n", oper_cfg.vpss_name);
	return 0;

fail3:
	release_mem_region(oper_cfg.r2->start, oper_cfg.len2);
fail2:
	iounmap(oper_cfg.vpss_bl_regs_base);
fail1:
	release_mem_region(oper_cfg.r1->start, oper_cfg.len1);
	return status;
}

static int vpss_remove(struct platform_device *pdev)
{
	iounmap(oper_cfg.vpss_bl_regs_base);
	release_mem_region(oper_cfg.r1->start, oper_cfg.len1);
	if (!strcmp(oper_cfg.vpss_name, "dm355_vpss")) {
		iounmap(oper_cfg.vpss_regs_base);
		release_mem_region(oper_cfg.r2->start, oper_cfg.len2);
	}
	return 0;
}

static struct platform_driver vpss_driver = {
	.driver = {
		.name	= "vpss",
		.owner = THIS_MODULE,
	},
	.remove = __devexit_p(vpss_remove),
	.probe = vpss_probe,
};

static void vpss_exit(void)
{
	platform_driver_unregister(&vpss_driver);
}

static int __init vpss_init(void)
{
	return platform_driver_register(&vpss_driver);
}
subsys_initcall(vpss_init);
module_exit(vpss_exit);